Why Buy Matched Cells?
#1
Why Buy Matched Cells?
Nowadays theres a lot of emphasis on charging and discharging equipment that does cells individually in a pack. The idea is that charging and discharging individually tailors to each individual cells characteristics. So given that, what is the point in putting together matched cells?
Aside from that most of the cells coming from today's factories are being produced to a more tighter tolerance such that the variance from one cell to another is very minimal. Yes, this could be debated but manufacturing technology for batteries has much improved since the early days of Sanyo 1200s.
Will such technology(ie Spintec ICC, Much-More, etc) eventually put the "matcher" out of business?
Please share your comments constructively.
Aside from that most of the cells coming from today's factories are being produced to a more tighter tolerance such that the variance from one cell to another is very minimal. Yes, this could be debated but manufacturing technology for batteries has much improved since the early days of Sanyo 1200s.
Will such technology(ie Spintec ICC, Much-More, etc) eventually put the "matcher" out of business?
Please share your comments constructively.
#2
Company Representative
iTrader: (2)
Actually the cells have more power than ever but the actual consistency within a case of cells isn't that good. We see a 40 second spread at 35amps. The voltage and IR is more consistent but there are some low voltage and higher IR cells within a case.
The price of loose unmatched and zapped cells is lower than matched packs but not much lower. You can get mid level packs from every matcher at a real good price and they are matched.
The price of loose unmatched and zapped cells is lower than matched packs but not much lower. You can get mid level packs from every matcher at a real good price and they are matched.
#3
You need to come match a few cases of cells......you will see how big the spread in voltage and runtime is.....
You will also to get to see the occasional cell that is so bad, its not even funny.....
Matched cells allow your pack to discharge during the run at the same levels.....give you the same feel from start to finish....no random drops you would see from unmatched cells.
All the new equipment does is allow you to maintain your batteries to keep them as close to the labels as possible.....and charged to optimal levels. No charger out there is going to turn a bad or medicore cell into a great one......the charger can only get it to its peak level.....if thats 426 seconds.....than thats what you will get, which won't give you optimal performance if the rest of the pack has 440 cells....
Later EddieO
You will also to get to see the occasional cell that is so bad, its not even funny.....
Matched cells allow your pack to discharge during the run at the same levels.....give you the same feel from start to finish....no random drops you would see from unmatched cells.
All the new equipment does is allow you to maintain your batteries to keep them as close to the labels as possible.....and charged to optimal levels. No charger out there is going to turn a bad or medicore cell into a great one......the charger can only get it to its peak level.....if thats 426 seconds.....than thats what you will get, which won't give you optimal performance if the rest of the pack has 440 cells....
Later EddieO
#4
Tech Elite
iTrader: (10)
With the batteries we have now a days (High voltage low IR)I don't see the point of really getting matched cells, There is a very minimal advantage of running a matched cells. I can't really tell the difference between my matched 3800's and my unmatched 3800's when running them,they both run consistent thru out the run with the same lap time. You just need to properly discharge and charge you packs. In a long run your expensive matched packs will become unmatched.
#6
Tech Master
Hi all,
I was wondering...How many cycles do you go through (average) to get the matched cells unmatched??
I was wondering...How many cycles do you go through (average) to get the matched cells unmatched??
#7
Registered User
Originally Posted by Jochim_18
With the batteries we have now a days (High voltage low IR)I don't see the point of really getting matched cells, There is a very minimal advantage of running a matched cells......
What about runtime? You don't mention it as a performance parameter and it is extremely important! In any given batch of cells, lets say IB4200SHV's; it is possible to see at least a 60 second (at 35-Amps) difference in runtime between cells throughout a batch. If assembled as an unmatched pack those same cells will charge and discharge with destructive disparity. During a charge cycle the cells will charge unevenly by 200 to 300 seconds or more. Then during the discharge cycle a similar relationship will occur with cells unevenly discharging by at least 60 seconds. Since it is a fact that more battery packs are destroyed by over discharging than any other factor, it follows the more closely the cells in a pack are matched the less likely any given cell will be damaged during the discharge cycle. Once a cell is damaged its capacity is reduced thus adding to the discrepancy noted above and the problem worsens with each additional cycle.
Originally Posted by Jochim_18
In a long run your expensive matched packs will become unmatched.
Last edited by SPC; 09-18-2006 at 08:53 PM.
#8
Tech Champion
iTrader: (17)
If you can search around the average price of a OK matched pack of 4200...it is around $40-50 each (6 cells)........for that kind of a price, I would let them to MATCH the cell for me instead of me buying 100 cells and find only 30-40 of them are able to be matched and the rest are for nothing...
For anykind of racing (club or major race) matched cells is a must have....I paid $100 for 3 packs of matched 4200 SHV (1.20v plus) from Hurricane Motorsport........come downs to $33.34 each, I cannot complaint for that price, and the performance are better then what I can imagine.
For anykind of racing (club or major race) matched cells is a must have....I paid $100 for 3 packs of matched 4200 SHV (1.20v plus) from Hurricane Motorsport........come downs to $33.34 each, I cannot complaint for that price, and the performance are better then what I can imagine.
#9
Tech Addict
iTrader: (1)
Okay the ad for Hurricane Motorsports is over now. Everyone can pay attention again! Hah!
More opinions here:
http://www.rctech.net/forum/showthread.php?t=126971
Danny/SMC, EddieO, It's be cool to get your opinions on this topic. I've always been curious.
More opinions here:
http://www.rctech.net/forum/showthread.php?t=126971
Originally Posted by Ben.C
Hi all,
I was wondering...How many cycles do you go through (average) to get the matched cells unmatched??
I was wondering...How many cycles do you go through (average) to get the matched cells unmatched??
#10
Originally Posted by SPC
Matched cells benefit everyone ....
....So why not get as much of a head start as you can on the inevitable order-to-disorder transformation?
....So why not get as much of a head start as you can on the inevitable order-to-disorder transformation?
#11
One thing that has me a little confused is apparently, that cells tend to get a little better as time goes on for the first few cycles.
If that is the case,maybe some in a given pack will improve more than others and therefore give you an unmatched pack?
Or is there a flaw in my thinking?
(It's probably going to be the latter guys )
If that is the case,maybe some in a given pack will improve more than others and therefore give you an unmatched pack?
Or is there a flaw in my thinking?
(It's probably going to be the latter guys )
#12
Big difference between matched cells and un-matched cells are:
"Matched cells will give you more punch and power for the first 2mins than un-matched cells. After 2mins, matched cells performed similar to un-matched cells. so, un-matched cells is enough for club race." said by Daisuke Yoshioka
"Matched cells will give you more punch and power for the first 2mins than un-matched cells. After 2mins, matched cells performed similar to un-matched cells. so, un-matched cells is enough for club race." said by Daisuke Yoshioka
#13
Awesome posts guys but I want to narrow the point down towards the relation of matched and unmatched packs with the new crop of Individual Cell Chargers and Dischargers.
SPC - I agree matched packs are necessary when dealing with the pack as a whole. That is why matching was necessary in the first place. However, when charging and discharging each cell within a pack individually wouldn't it negate the need for matching?
Also, if one were to use one of those speed controls that can adjust voltage cutoff and set it for a slightly higher voltage such that to prevent overdischarging of a weak cell in a pack, wouldn't that prolong the life of the pack as well?
The question isn't about do I need matched packs, it is more like "Do I need matched packs if I charge and discharge my cells individually?"
Please comment further.
BTW, Mr. Howart, if you are out there, I would really appreciate your opinion on this. Thanks.
Originally Posted by SPC
.... If assembled as an unmatched pack those same cells will charge and discharge with destructive disparity. During a charge cycle the cells will charge unevenly by 200 to 300 seconds or more. Then during the discharge cycle a similar relationship will occur with cells unevenly discharging by at least 60 seconds. Since it is a fact that more battery packs are destroyed by over discharging than any other factor, it follows the more closely the cells in a pack are matched the less likely any given cell will be damaged during the discharge cycle. ...
Also, if one were to use one of those speed controls that can adjust voltage cutoff and set it for a slightly higher voltage such that to prevent overdischarging of a weak cell in a pack, wouldn't that prolong the life of the pack as well?
The question isn't about do I need matched packs, it is more like "Do I need matched packs if I charge and discharge my cells individually?"
Please comment further.
BTW, Mr. Howart, if you are out there, I would really appreciate your opinion on this. Thanks.
#14
Registered User
Originally Posted by YR4Dude
..... However, when charging and discharging each cell within a pack individually wouldn't it negate the need for matching?
The question isn't about do I need matched packs, it is more like "Do I need matched packs if I charge and discharge my cells individually?"
The question isn't about do I need matched packs, it is more like "Do I need matched packs if I charge and discharge my cells individually?"
When you purchase matched cells you not only get the obvious matching you also get cells that have been pre-tested, tested for duds, tested for failures and tested for weak cells. I don't know of any battery supplier selling unmatched packs who pre-tests all of the cells they sale. Do you?
Originally Posted by YR4Dude
..... Also, if one were to use one of those speed controls that can adjust voltage cutoff and set it for a slightly higher voltage such that to prevent overdischarging of a weak cell in a pack, wouldn't that prolong the life of the pack as well?
Last edited by SPC; 09-18-2006 at 01:51 PM.
#15
Tech Apprentice
I'm no expert but ...
You get what you pay for.
You get what you pay for.